UVM Theses and Dissertations
Format:
Print
Author:
Sullivan, Mažeika
Dept./Program:
Natural Resources
Year:
2004
Degree:
Ph. D.
Abstract:
The connections between fluvial geomorphology and biotic condition have been identified as critical in understanding stream and river biotic integrity, and in developing efficient management and conservation strategies. River channels exhibit predictable patterns of morphology along their length. The amount of water and sediments introduced into the channel, the size of the sediments, and the topography of the landscape through which a river flows shape these morphological patterns. Changes in any of these governing factors are expected to produce deviations in the morphological condition of a river reach. Despite the potential for fluvial geomorphology to govern biotic condition, there have been few direct tests of the associations between geomorphic condition and riverine aquatic biota.
To this end, I explored potential relationships between fluvial geomorphology, ins-stream habitat, and aquatic biota at 83 river reaches and twenty-four floodplain sites distributed across eighteen Vermont streams and rivers. I used prominent stream and river classification systems, geomorphic condition assessments, and measures of channel dimensions to evaluate fluvial geomorphology. Habitat assessments were primarily based on rapid bioassessment protocols. While the belted kingfisher (Ceryle alcyan) served as a focal species; aquatic macroinvertebrate, fish, and crayfish communities were also used to assess biotic condition. Multivariate methods were then used to relate the physical measures to biotic condition. My results suggest that geomorphic condition and characteristics have strong impacts on biotic condition. I found that habitat quality and heterogeneity were closely tied to stream stability, with stable reaches supporting better habitat than unstable reaches (r = 0.624, p < 0.006, n = 18).
To this end, I explored potential relationships between fluvial geomorphology, ins-stream habitat, and aquatic biota at 83 river reaches and twenty-four floodplain sites distributed across eighteen Vermont streams and rivers. I used prominent stream and river classification systems, geomorphic condition assessments, and measures of channel dimensions to evaluate fluvial geomorphology. Habitat assessments were primarily based on rapid bioassessment protocols. While the belted kingfisher (Ceryle alcyan) served as a focal species; aquatic macroinvertebrate, fish, and crayfish communities were also used to assess biotic condition. Multivariate methods were then used to relate the physical measures to biotic condition. My results suggest that geomorphic condition and characteristics have strong impacts on biotic condition. I found that habitat quality and heterogeneity were closely tied to stream stability, with stable reaches supporting better habitat than unstable reaches (r = 0.624, p < 0.006, n = 18).